CO2 Elevation

The chest tubes came out yesterday. It’s so nice to be able to just scoop Charlotte out of her crib, even if she’s still attached to what I call “spaghetti”—monitors for respiration rate, pulse, blood oxygenation, heart rate; arterial line through which blood is drawn (so they don’t have to prick her every time); main line (through which medications are delivered); and an NG tube for feeding.

Since the ventilator was removed, Charlotte has been on oxygen, delivered through a nasal tube called a cannula (like what you see on TV all time). For first day, all of her tests came back normal. Then, she was placed on the methadone treatment—not only was she stoned out of her mind (the medical term, I swear J), but her breathing got more rapid. I noticed all day on the 29th , that her respiration rate was consistently higher than we thought it should be. She didn’t seem uncomfortable and the nurses at first thought this was the normal high/low breathing pattern of a newborn.

That evening we got a phone call at 11:30 pm from her nurse. My heart stopped. Literally. It turned out that a test that evening showed elevated CO2 levels. Translation: her breathing was more labored and her blood gasses are not properly balanced. Because she did not seem to be “retracting” (using non-breathing muscles to breath), the first step was to put her on a Vapotherm cannula. This delivers humidified oxygen with a higher pressure than the regular cannula, opening her airways for more efficient oxygen delivery. Michelle, the nurse on duty, wanted to let us know so that we wouldn’t be surprised at a new machine in the room.

So far (since that midnight call), Charlotte’s CO2 levels have come down, but not quite enough. It seemed that she’s plateaued. This morning, the doctors told Philippe that they will go slow to treat. They’re giving her time to figure it out, recover, and her blood gasses right on her own. Chalking it up to slow recovery because she’s so tiny, I think. We were worried, though, because they implied that the next step would be to re-intubate her (put the ventilator back in).

Philippe and I have been frustrated that they were treating the symptom, not finding a cause. Well….Philippe just called and it seems we have a cause for the CO2 elevation and, now, a treatment that is working. The theory is that Charlotte is experiencing metabolic alkalosis, an inability to regulate her pH level, brought on in her case by the 2 weeks of diuretics (Lasix) she’s been getting. Since the attending and the nurse came up with this, Charlotte has gotten two doses of ammonium chloride and her CO2 level has come down steadily. Since it’s the night crew that is determining this, we’ll have to see if the primary doctors want to continue this course of action in the morning. But for now, Philippe says she looks more comfortable and relaxed than she has in a few days.

A factoid:
In the US: Metabolic alkalosis is the most common acid-base disturbance observed in hospitalized patients, accounting for approximately 50% of all acid-base disorders.